Thermodynamics · Chemistry · TS EAMCET

The $C_p$ of an ideal gas is $10314 \mathrm{Jmol}^{-1} \mathrm{~K}^{-1}$. One mole of this gas is expanded against a constant pressure of $p \mathrm{~atm}$. The change in temperature during expansion is 1.0 K . The value of $q$ (in J ) and $\Delta H$ (in $\mathrm{Jmol}^{-1}$ ) are respectively.

The entropy and enthalpy changes for the reaction $\mathrm{CO}(\mathrm{g})+\mathrm{H}_2 \mathrm{O}(\mathrm{g}) \rightleftharpoons \mathrm{CO}_2(\mathrm{~g})+\mathrm{H}_2(\mathrm{~g})$ at 300 K and 1 atm are respectively $-42.4 \mathrm{JK}^{-1}$ and -41.2 kJ . The temperature at which the reaction will go in the reverse direction is

Which of the following processes are reversible?

I. Vaporisation of a liquid at its boiling point.

II. Expansion of gas into vacuum.

III. Transformation of a solid substance into liquid at its melting point.

At 298 K , if the standard Gibbs energy change $\Delta_r G^{\circ}$ of a reaction is -115 kJ , the value of $\log _{10} K_p$ will be $\left(R=8.314 \mathrm{JK}^{-1} \mathrm{~mol}^{-1}\right)$

One mole of an ideal gas at 300 K and 20 atm expands to 2 atm under isothermal and reversible conditions. The work done by the gas is $-x \mathrm{~kJ} \mathrm{~mol}^{-1}$. The value of $x$ is $\left(R=8.3 \mathrm{~J} \mathrm{~K}^{-1} \mathrm{~mol}^{-1}\right)$

At 298 K , the enthalpy change ( in kJ ) for the reaction given below is

$$ \mathrm{CH}_4(g)+\mathrm{O}_2(g) \longrightarrow \mathrm{C}(s)+2 \mathrm{H}_2 \mathrm{O}(l) $$

$$ \begin{aligned} Given:\mathrm{H}_2(g)+\frac{1}{2} \mathrm{O}_2(g) & \longrightarrow \mathrm{H}_2 \mathrm{O}(l) ; \Delta H^{\ominus}=-286 \mathrm{~kJ} \\ \mathrm{C}(s)+\mathrm{O}_2(g) & \longrightarrow \mathrm{CO}_2(g) ; \Delta H^{\ominus}=-394 \mathrm{~kJ} \\ \mathrm{CH}_4(g)+2 \mathrm{O}_2(g) & \longrightarrow \mathrm{CO}_2(g)+2 \mathrm{H}_2 \mathrm{O}(l) \Delta H^{\ominus}=-890 \mathrm{~kJ}\end{aligned} $$

At $T(\mathrm{~K}) 2$ mole of an ideal gas is allowed to expand reversibly and isothermally from a pressure of 10 atmospheres to 1 atmosphere. The work done (in kJ ) is $\left(R=8.3 \mathrm{JK}^{-1} \mathrm{~mol}^{-1}\right)$

For the reaction at $25^{\circ} \mathrm{C}, X_2 \mathrm{O}_4(l) \longrightarrow 2 \mathrm{XO}_2(g), \Delta U$ and $\Delta S$ are 2.1 k cal and $20 \mathrm{cal} / \mathrm{K}$ respectively. What is $\Delta \mathrm{G}$ for the reaction at the same temperature? ( $R=2 \mathrm{cal} \mathrm{K}^{-1} \mathrm{~mol}^{-1}$ )

In. Observe the following properties.

1. Molar volume

II. Mass

III. Internal energy

IV. Volume

v. Enthalpy

VI. Temperature

VII. Density

The intensive properties in the above list are

Enthalpy of formation of $\mathrm{CO}(g), \mathrm{CO}_2(g)$ are -110 , $-393 \mathrm{~kJ} \mathrm{~mol}^{-1}$ respectively. The enthalpy of combustion of CO (in $\mathrm{kJ} \mathrm{mol}^{-1}$ ) is

The enthalpies of formation of gaseous $\mathrm{N}_2 \mathrm{O}$ and NO at 298 K are 82.0 and $90.0 \mathrm{~kJ} \mathrm{~mol}^{-1}$ respectively. The enthalpy change of the reaction

$\mathrm{N}_2 \mathrm{O}(g)+\frac{1}{2} \mathrm{O}_2(g) \longrightarrow 2 \mathrm{NO}(g)$ is

The bond enthalpies of heavy hydrogen, $\mathrm{O}-\mathrm{O}$ and $\mathrm{D}-\mathrm{O}$ are $+400,+498$ and $+490 \mathrm{kJmol}^{-1}$, respectively. The $\Delta_r H^{\circ}$ of the reaction to produce $\mathrm{D}_2 \mathrm{O}$ is

In the reaction, $\mathrm{H}_2 \mathrm{O}(l) E \longrightarrow \mathrm{H}_2 \mathrm{O}(s)$ at $0^{\circ} \mathrm{C}$ and 1 atom, the internal energy change is $-41 \mathrm{~kJ} / \mathrm{mol}$. What will be the value of molar enthalpy change?

The correct order of " $\Delta H_f^{\circ}$ " values of diamond (I), graphite (II) and fullerene (III) is

An air bag on adiabatic expansion undergoes $5 \%$ increase in its volume. The percentage change in pressure is $\left[\gamma_{\text {air }}=1.4\right]$

Given,

$$ \mathrm{H}_2(g)+\frac{1}{2} \mathrm{O}_2(g) \longrightarrow \mathrm{H}_2 \mathrm{O}(l) ; \Delta H=-285 \mathrm{~kJ} $$

$$ \begin{aligned} & \mathrm{N}_2 \mathrm{O}_5(g)+\mathrm{H}_2 \mathrm{O}(l) \longrightarrow 2 \mathrm{HNO}_3(l) ; \Delta H=-76.6 \mathrm{~kJ} \\ & \mathrm{~N}_2(g)+3 \mathrm{O}_2(g)+\mathrm{H}_2(g) \longrightarrow 2 \mathrm{HNO}_3(l) ; \\ & \Delta H=-348.2 \mathrm{~kJ} \end{aligned} $$

Calculate the $\Delta \mathrm{H}$ of $2 \mathrm{~N}_2(\mathrm{~g})+5 \mathrm{O}_2(\mathrm{~g}) \longrightarrow 2 \mathrm{~N}_2 \mathrm{O}_5(\mathrm{~g})$.

The change in enthalpy $[\Delta H]$ in $\mathrm{kJ} \mathrm{mol}^{-1}$ for the reaction, $\mathrm{Mg}+2 \mathrm{~F} \longrightarrow \mathrm{MgF}_2$ is

Given, electron affinity of $\mathrm{F}=328 \mathrm{~kJ} \mathrm{~mol}^{-1}$,

IE ${ }_1$ of $\mathrm{Mg}=737 \mathrm{kJmol}^{-1}, \mathrm{IE}_2$ of $\mathrm{Mg}=1451 \mathrm{kJmol}^{-1}$

A certain mass of a gas was brought from state $A$ to $B$ by following three different paths, namely 1,2 and 3 , respectively. Which of the following relations is correct for the work done?

Among the following given substances, the one with zero $\Delta_f H^{\circ}$ is

If 92 g Na reacts with water in open vessel at 300 K . What is the value of work done?

[Assume ideal nature of the gaseous product.]

For the reactions,

$$ \begin{aligned} 2 \mathrm{Cl}(g) & \longrightarrow \mathrm{Cl}_2(g) \\ \mathrm{CO}_2(g) & \longrightarrow \mathrm{CO}(g)+\frac{1}{2} \mathrm{O}_2(g) \end{aligned} $$

What are the signs of $\Delta S$, respectively?

Which of the following statement is correct?

$\Delta_r H$ of which reaction correctly represents the lattice enthalpy of $\mathrm{NaCl}(s)$ ?

In which of the processes, the entropy will decrease

Which of the following statements regarding the first law of thermodynamics is correct?

Find the value of the equilibrium constant $(K)$ of a reaction at 300 K , when standard Gibbs free energy change is $-25 \mathrm{~kJ} \mathrm{~mol}^{-1}$ ? (Consider $R=8.33 \mathrm{Jmol}^{-1} \mathrm{~K}^{-1}$ )

What will be the $\Delta U$ value, when one mole of oxygen $\left(\mathrm{O}_2\right)$ is going from $-20^{\circ} \mathrm{C}$ to $40^{\circ} \mathrm{C}$ at constant volume? (Molar heat capacity for oxygen $\simeq 20.8 \mathrm{~J} \mathrm{~mol}^{-1} \mathrm{~K}^{-1}$ )

$\Delta H$ and $\Delta S$ for a reaction are $+30.0 \mathrm{~kJ} \mathrm{~mol}^{-1}$ and 0.06 $\mathrm{kJK}^{-1} \mathrm{~mol}^{-1}$ at 1 atm pressure. The temperature at which free energy change is equal to zero and nature of the reaction below this temperature are